WO2022185650A1 - Information processing device, information processing method, and information processing program - Google Patents

Abstract

When an information processing device according to the present invention reads a plurality of packed objects, in which a plurality of objects are combined according to a predetermined rule, from an original magnetic tape in which the packed objects are recorded, and then records the read packed objects onto a magnetic tape to which the packed objects are to be transferred, the information processing device, according to a rule, combines a plurality of objects that are included in a plurality of packed objects in which the percentage of deleted objects is greater than or equal to a predetermined threshold and that are not given deletion information, so as to carry out a re-packing process for generating packed objects.

Description

Information processing device, information processing method, and information processing program

The present disclosure relates to an information processing device, an information processing method, and an information processing program.

Japanese Patent Application Laid-Open No. 2015-103033 discloses a technique for deleting unnecessary data or replacing it with a zero value during magnetic tape reclamation.

With magnetic tape, when deleting an object, deletion information indicating that it has been deleted may be added to the object, and the object itself may not be deleted from the magnetic tape. In this case, as in the technique described in Japanese Patent Application Laid-Open No. 2015-103033, objects to which deletion information is assigned in the source magnetic tape are not migrated, and only objects to which deletion information is not assigned are transferred to the destination magnetic tape. By migrating to tape, you can increase the amount of free space on the destination magnetic tape. Hereinafter, such migration processing for increasing the free space of the magnetic tape will be referred to as "reclamation processing".

Also, when recording objects on a magnetic tape, recording is performed in units of objects (hereinafter referred to as "packed objects") in which multiple objects are grouped according to predetermined rules. This is done for the purpose of reducing the overhead caused by issuing a command for instructing the recording of an object to the tape drive from the control device that controls the tape drive.

When reclaiming a magnetic tape on which objects are recorded in units of packed objects, the following problems may occur if the packed objects that have been deleted with deletion information for each packed object are recorded on the migration destination magnetic tape. be. This is not efficient because it can create packed objects that are too small.

The present disclosure has been made in view of the above circumstances, and provides an information processing apparatus, information processing method, and information processing program capable of efficiently performing reclamation processing of a magnetic tape on which objects are recorded in units of packed objects. intended to provide

An information processing apparatus according to the present disclosure is an information processing apparatus including at least one processor, and the processor is a migration source magnetic tape on which a plurality of packed objects in which a plurality of objects are grouped according to a predetermined rule are recorded. When reading a packed object from and recording the read packed object on a destination magnetic tape, an object included in a plurality of packed objects whose deletion rate of the object in the packed object is equal to or greater than a predetermined threshold, A repacking process is performed to generate a packed object by grouping a plurality of objects to which deletion information is not assigned according to the above rules.

Note that, in the information processing apparatus of the present disclosure, the processor deletes objects to which deletion information is assigned for packed objects whose deletion rate is less than a threshold, and deletes objects to which deletion information is not assigned for the deleted objects. You can also create a packed object with .

Further, in the information processing apparatus of the present disclosure, the processor selects, among packed objects whose deletion rate is equal to or greater than a threshold, packed objects recorded at a position where the read time is within a second threshold as processing targets in one repacking process. may be

Further, in the information processing apparatus of the present disclosure, the processor performs one-time repacking processing on packed objects whose deletion rate is equal to or greater than a threshold and whose capacity is equal to or smaller than the free space of a storage area for temporarily storing packed objects. It may be processed.

Also, in the information processing apparatus of the present disclosure, the rule used in the repacking process may be the same rule as the rule used when the packed object to be repacked is generated.

Also, in the information processing apparatus of the present disclosure, the rules used in the repacking process may be different from the rules used when the packed objects to be repacked are generated.

Further, in the information processing apparatus of the present disclosure, the deletion rate is the ratio of the number of objects to which deletion information is assigned to the total number of objects included in the packed object, or the ratio of the number of objects to which deletion information is assigned to the total size of the objects included in the packed object. It may be a ratio of the total size of the objects that have been drawn.

Further, the information processing method of the present disclosure reads the packed objects from the source magnetic tape on which a plurality of packed objects in which the plurality of objects are grouped according to a predetermined rule is recorded, and transfers the read packed objects to the destination magnetic tape. When recording on a magnetic tape, a plurality of objects included in a plurality of packed objects whose deletion rate of the objects in the packed objects is equal to or greater than a predetermined threshold value and to which deletion information is not attached are processed according to the above rules. A processor included in the information processing apparatus executes a process of generating a packed object by putting together.

Further, the information processing program of the present disclosure reads the packed objects from the migration source magnetic tape on which a plurality of packed objects in which the plurality of objects are grouped according to a predetermined rule is recorded, and transfers the read packed objects to the migration destination. When recording on a magnetic tape, a plurality of objects included in a plurality of packed objects whose deletion rate of the objects in the packed objects is equal to or greater than a predetermined threshold value and to which deletion information is not attached are processed according to the above rules. This is for causing a processor included in the information processing apparatus to execute a process of generating a packed object by putting together.

According to the present disclosure, it is possible to efficiently perform reclamation processing for magnetic tapes on which objects are recorded in units of packed objects.

1 is a block diagram showing an example of the configuration of an information processing system; FIG. FIG. 4 is a diagram for explaining an object; FIG. FIG. 4 is a diagram for explaining a packed object; FIG. It is a block diagram which shows an example of the hardware constitutions of an information processing apparatus. 1 is a block diagram showing an example of a functional configuration of an information processing device; FIG. FIG. 10 is a diagram for explaining reclamation processing when a deletion rate is equal to or greater than a threshold; FIG. 10 is a diagram for explaining reclamation processing when a deletion rate is less than a threshold; FIG. 11 is a flow chart showing an example of packed object re-creation processing; FIG. FIG. 11 is a diagram for explaining packed objects processed at once according to a modification;

Embodiments for implementing the technology of the present disclosure will be described in detail below with reference to the drawings.

First, the configuration of an information processing system 10 according to the present embodiment will be described with reference to FIG. As shown in FIG. 1, the information processing system 10 includes an information processing device 12 and a tape library 14 . Examples of the information processing device 12 include a server computer and the like.

The tape library 14 comprises a plurality of slots (not shown) and a plurality of tape drives 18, each slot storing a magnetic tape T as an example of a recording medium. Each tape drive 18 is connected to the information processing device 12 . The tape drive 18 writes data to or reads data from the magnetic tape T under the control of the information processing device 12 . An example of the magnetic tape T is an LTO (Linear Tape-Open) tape.

When the information processing device 12 writes data to or reads data from the magnetic tape T, the magnetic tape T to be written or read is loaded from the slot into the predetermined tape drive 18 . After data has been written or read from the magnetic tape T loaded in the tape drive 18, the magnetic tape T is unloaded from the tape drive 18 to the slot in which it was originally stored.

In this embodiment, as an example, as shown in FIG. 2, a unit handling data to be recorded on the magnetic tape T includes data to be stored by the user, such as document data and image data, and metadata related to the data. A form example to which an object is applied will be described. In the example of FIG. 2, the metadata is written as "meta". A storage system that handles this object is called an object storage system. The metadata includes, for example, object identification information such as object keys, object names, data sizes, and attribute information such as time stamps. The recording order of the data and the metadata when recording the object on the magnetic tape T is not particularly limited, and may be the order of the metadata and the data, or the order of the data and the metadata.

In this embodiment, as shown in FIG. 3 as an example, objects are recorded on the magnetic tape T in units of packed objects in which a plurality of objects are grouped according to a predetermined rule (hereinafter referred to as "packing rule"). be. This is intended to reduce overhead caused by issuing a command for recording to the tape drive 18 when the information processing device 12 records an object on the magnetic tape T. FIG. "Obj" in FIG. 3 represents an object. Although FIG. 3 shows an example in which one packed object includes four objects, the present invention is not limited to this. One packed object may contain three or less objects, or may contain five or more objects. Also, the number of objects included in a packed object may not be uniform.

Examples of packing rules include rules such as grouping multiple objects that contain data with the same extension into the same packed object, or grouping multiple objects that are likely to be read at the same time into the same packed object. Examples of packing rules include a rule that a plurality of objects are grouped into one packed object so that the size of one packed object is greater than or equal to a predetermined lower limit value and less than an upper limit value.

Next, the hardware configuration of the information processing device 12 according to this embodiment will be described with reference to FIG. As shown in FIG. 4, the information processing device 12 includes a CPU (Central Processing Unit) 20, a memory 21 as a temporary storage area, and a non-volatile storage section 22. FIG. The information processing device 12 also includes a display 23 such as a liquid crystal display, an input device 24 such as a keyboard and a mouse, a network I/F (InterFace) 25 connected to a network, and an external I/F to which each tape drive 18 is connected. Including F26. CPU 20 , memory 21 , storage unit 22 , display 23 , input device 24 , network I/F 25 and external I/F 26 are connected to bus 27 .

The storage unit 22 is implemented by a HDD (Hard Disk Drive), SSD (Solid State Drive), flash memory, or the like. An information processing program 30 is stored in the storage unit 22 as a storage medium. The CPU 20 reads out the information processing program 30 from the storage unit 22 , expands it in the memory 21 , and executes the expanded information processing program 30 .

The storage unit 22 also stores an object management DB (DataBase) 32 for managing information about objects recorded on the magnetic tape T. The object management DB 32 stores, for each object, the size of the object, the name of the object, the information indicating what number of the packed object the object is, and the identification information of the magnetic tape T on which the object is recorded. be done. Further, deletion information indicating that the object has been deleted is attached to the object deleted by the user in the object management DB 32 .

By the way, since it is difficult to delete only a specific object from the magnetic tape T, the deletion information is attached to the object deleted by the user. That is, even an object that is deleted by the user consumes space on the magnetic tape. Therefore, the free space of the magnetic tape T is secured by reclamation processing. The information processing apparatus 12 according to the present embodiment has a function for efficiently performing reclamation processing of the magnetic tape T on which objects are recorded in units of packed objects. Hereinafter, the magnetic tape T from which objects are transferred in the reclamation process will be referred to as "magnetic tape T1", and the magnetic tape T to which objects will be transferred will be referred to as "magnetic tape T2". In the reclamation process, one magnetic tape T1 and one magnetic tape T2 may be associated, or a plurality of magnetic tapes T1 and one magnetic tape T2 may be associated. . Further, the same magnetic tape T may be used as the magnetic tape T1 and the magnetic tape T2. An example in which one magnetic tape T1 and one magnetic tape T2 are provided and different magnetic tapes T are described below.

Next, with reference to FIG. 5, the functional configuration of the information processing device 12 according to this embodiment will be described. As shown in FIG. 5 , the information processing device 12 includes a derivation section 40 and a control section 42 . The CPU 20 functions as a derivation unit 40 and a control unit 42 by executing the information processing program 30 .

The derivation unit 40 refers to the object management DB 32 and derives the deletion rate of objects in the packed objects for all packed objects recorded on the magnetic tape T1. The deletion rate represents the rate at which objects within the packed object are deleted. Specifically, the derivation unit 40 derives the ratio of the total size of the objects to which the deletion information is added to the total size of the objects included in the packed object as the deletion ratio. Note that the deriving unit 40 may derive the ratio of the number of objects to which deletion information is added to the total number of objects included in the packed object as the deletion rate.

The control unit 42 controls reading of packed objects from the magnetic tape T1 on which a plurality of packed objects are recorded, and controls recording of the read packed objects on the magnetic tape T2. At this time, as described below, the control unit 42 switches processing according to the deletion rate of packed objects.

As an example, as shown in FIG. 6, the control unit 42 selects a plurality of packed objects each having a deletion rate derived by the derivation unit 40 equal to or greater than a threshold TH1 and not attached with deletion information. A process (hereinafter referred to as "repacking process") is performed to generate a packed object by grouping objects according to the packing rule. "Obj" in FIGS. 6 and 7 represents an object, and an object described as "(deletion)" represents an object to which deletion information is added. In this embodiment, the packing rule used in this repacking process is the same rule used when the packed object to be repacked is generated. Note that the packing rule used in this repacking process may be different from the rule used when the packed object to be repacked is generated. Information indicating which packing rule was used when each packed object was generated may be stored in the object management DB 32, or may be included in the header of the packed object.

As shown in FIG. 6, by the repacking process, the packing of a plurality of packed objects is temporarily released, and among all the objects included in the plurality of packed objects, the objects excluding the object to which the deletion information is added are repacked. be done.

As an example, as shown in FIG. 7, the control unit 42 deletes the objects to which deletion information has been added for packed objects whose deletion rate derived by the deriving unit 40 is less than the threshold TH1, and separates the deleted objects. , generate a packed object containing objects without deletion information. As a result, a packed object is generated in which only the objects to which the deletion information included in the packed object has been deleted are deleted.

Next, the operation of the information processing device 12 according to this embodiment will be described with reference to FIG. The CPU 20 executes the information processing program 30 to execute the packed object re-creation process shown in FIG. The packed object re-creation process shown in FIG. 8 is executed, for example, when an execution instruction is input by the user. At this time, the identification information of the magnetic tapes T1 and T2 to be processed is also input.

At step S10 in FIG. 8, the derivation unit 40 refers to the object management DB 32 as described above, and derives the deletion rate of objects in the packed objects for all packed objects recorded on the magnetic tape T1. In step S12, the control unit 42 performs control to read all packed objects recorded on the magnetic tape T1.

In step S14, as described above, the control unit 42 performs repacking processing for a plurality of packed objects whose deletion ratios read in step S12 and derived in step S10 are equal to or greater than the threshold TH1. In step S16, the control unit 42 deletes the objects to which the deletion information is added for the packed objects read in step S12 and derived in step S10 for which the deletion rate is less than the threshold TH1, and deletes the deleted objects. Generates a packed object containing objects without deletion information.

At step S18, the control unit 42 performs control to record the packed objects generated at steps S14 and S16 on the magnetic tape T2. When the process of step S18 ends, the packed object re-creation process ends.

As described above, according to the present embodiment, it is possible to efficiently perform reclamation processing of the magnetic tape T on which objects are recorded in units of packed objects.

In the above-described embodiment, the control unit 42 selects, among packed objects whose deletion rate is equal to or greater than the threshold TH1, packed objects recorded at positions where the reading time is within the threshold TH2 as processing targets in one repacking process. good too. In this case, as shown in FIG. 9 as an example, a plurality of packed objects recorded at relatively close positions and having a deletion rate equal to or higher than the threshold TH1 are processed in one repacking process. The dashed arrows in FIG. 9 represent the relative movement path of the magnetic head with respect to the magnetic tape T. In FIG. Also, "PO" in FIG. 9 represents a packed object. In the example of FIG. 9, a plurality of packed objects within each dashed-line rectangle are processed in one repacking process.

Further, in the above-described embodiment, the control unit 42, among packed objects whose deletion rate is equal to or greater than the threshold value TH1, removes packed objects whose deletion rate is equal to or less than the free space of the storage area for temporarily storing packed objects in one repacking process. It may be processed. As a storage area for temporarily storing the packed object in this case, for example, the storage section 22 for temporarily storing the object read from the magnetic tape T1 by the control section 42 can be mentioned.

Further, in the above embodiment, for example, as a hardware structure of a processing unit that executes various processes such as the derivation unit 40 and the control unit 42, the following various processors can be used. can be done. As described above, the various processors include, in addition to the CPU, which is a general-purpose processor that executes software (programs) and functions as various processing units, circuits such as FPGAs (Field Programmable Gate Arrays), etc. Programmable Logic Device (PLD) which is a processor whose configuration can be changed, ASIC (Application Specific Integrated Circuit) etc. Circuits, etc. are included.

One processing unit may be composed of one of these various processors, or a combination of two or more processors of the same type or different types (for example, a combination of multiple FPGAs, a combination of a CPU and an FPGA). combination). Also, a plurality of processing units may be configured by one processor.

As an example of configuring a plurality of processing units with a single processor, first, as represented by computers such as clients and servers, a single processor is configured by combining one or more CPUs and software. There is a form in which a processor functions as multiple processing units. Second, as typified by System on Chip (SoC), etc., there is a form of using a processor that realizes the functions of the entire system including multiple processing units with a single IC (Integrated Circuit) chip. be. In this way, the various processing units are configured using one or more of the above various processors as a hardware structure.

Furthermore, as the hardware structure of these various processors, more specifically, an electric circuit combining circuit elements such as semiconductor elements can be used.

Also, in the above embodiment, the information processing program 30 has been pre-stored (installed) in the storage unit 22, but the present invention is not limited to this. The information processing program 30 is provided in a form recorded on a recording medium such as a CD-ROM (Compact Disc Read Only Memory), a DVD-ROM (Digital Versatile Disc Read Only Memory), and a USB (Universal Serial Bus) memory. good too. Further, the information processing program 30 may be downloaded from an external device via a network.

The disclosure of Japanese Patent Application No. 2021-032100 filed on March 1, 2021 is incorporated herein by reference in its entirety. In addition, all publications, patent applications, and technical standards mentioned herein are to the same extent as if each individual publication, patent application, or technical standard were specifically and individually noted to be incorporated by reference. , incorporated herein by reference.

Claims (9)

An information processing device comprising at least one processor,
The processor
When reading a packed object from a source magnetic tape on which a plurality of packed objects in which a plurality of objects are grouped according to a predetermined rule are recorded, and recording the read packed object on a destination magnetic tape,
A packed object is generated by grouping a plurality of objects included in a plurality of packed objects whose deletion rate of the objects in the packed object is equal to or higher than a predetermined threshold and to which deletion information is not assigned according to the rule. An information processing device that performs repacking processing. The processor
1. For packed objects whose deletion rate is less than the threshold, the objects to which deletion information has been added are deleted, and a packed object containing objects to which deletion information has not been added is generated for the deleted objects. The information processing device according to . The processor
3. The packed object according to claim 1 or 2, wherein among the packed objects whose deletion rate is equal to or greater than the threshold, the packed object recorded at a position where the reading time is within the second threshold is processed in one repacking process. information processing equipment. The processor
Among the packed objects whose deletion rate is equal to or greater than the threshold value, packed objects that are equal to or smaller than the free space of a storage area for temporarily storing the packed objects are subjected to one-time repacking processing. 4. The information processing apparatus according to any one of 3. The information processing apparatus according to any one of claims 1 to 4, wherein a rule used in the repacking process is the same rule as a rule used when a packed object to be repacked is generated. The information processing apparatus according to any one of claims 1 to 4, wherein a rule used in the repacking process is a rule different from a rule used when a packed object to be repacked is generated. . The deletion rate is the ratio of the number of objects to which deletion information is added to the total number of objects included in the packed object, or the ratio of the total size of the objects to which deletion information is added to the total size of the objects included in the packed object. The information processing apparatus according to any one of claims 1 to 6. When reading a packed object from a source magnetic tape on which a plurality of packed objects in which a plurality of objects are grouped according to a predetermined rule are recorded, and recording the read packed object on a destination magnetic tape,
A packed object is generated by grouping a plurality of objects included in a plurality of packed objects whose deletion rate of the objects in the packed object is equal to or higher than a predetermined threshold and to which deletion information is not assigned according to the rule. An information processing method in which a processor included in an information processing apparatus executes processing. When reading a packed object from a source magnetic tape on which a plurality of packed objects in which a plurality of objects are grouped according to a predetermined rule are recorded, and recording the read packed object on a destination magnetic tape,
A packed object is generated by grouping a plurality of objects included in a plurality of packed objects whose deletion rate of the objects in the packed object is equal to or higher than a predetermined threshold and to which deletion information is not assigned according to the rule. An information processing program for causing a processor included in an information processing device to execute processing.

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